String.prototype.trim = function(){
	return this.replace(/^\s+|\s+$/g, '');
}

if (!document.querySelectorAll) {
    document.querySelectorAll = function (selectors) {
        var style = document.createElement('style'), elements = [], element;
        document.documentElement.firstChild.appendChild(style);
        document._qsa = [];

        style.styleSheet.cssText = selectors + '{x-qsa:expression(document._qsa && document._qsa.push(this))}';
        window.scrollBy(0, 0);
        style.parentNode.removeChild(style);

        while (document._qsa.length) {
            element = document._qsa.shift();
            element.style.removeAttribute('x-qsa');
            elements.push(element);
        }
        document._qsa = null;
        return elements;
    };
}

if (!document.querySelector) {
    document.querySelector = function (selectors) {
        var elements = document.querySelectorAll(selectors);
        return (elements.length) ? elements[0] : null;
    };
}

// 用于在IE6和IE7浏览器中，支持Element.querySelectorAll方法
var qsaWorker = (function () {
    var idAllocator = 10000;

    function qsaWorkerShim(element, selector) {
        var needsID = element.id === "";
        if (needsID) {
            ++idAllocator;
            element.id = "__qsa" + idAllocator;
        }
        try {
            return document.querySelectorAll("#" + element.id + " " + selector);
        }
        finally {
            if (needsID) {
                element.id = "";
            }
        }
    }

    function qsaWorkerWrap(element, selector) {
        return element.querySelectorAll(selector);
    }

    // Return the one this browser wants to use
    return document.createElement('div').querySelectorAll ? qsaWorkerWrap : qsaWorkerShim;
})();



// Array.prototype.indexOf
if (!Array.prototype.indexOf) {
  Array.prototype.indexOf = function(searchElement, fromIndex) {

    var k;

    // 1. Let O be the result of calling ToObject passing
    //    the this value as the argument.
    if (this == null) {
      throw new TypeError('"this" is null or not defined');
    }

    var O = Object(this);

    // 2. Let lenValue be the result of calling the Get
    //    internal method of O with the argument "length".
    // 3. Let len be ToUint32(lenValue).
    var len = O.length >>> 0;

    // 4. If len is 0, return -1.
    if (len === 0) {
      return -1;
    }

    // 5. If argument fromIndex was passed let n be
    //    ToInteger(fromIndex); else let n be 0.
    var n = +fromIndex || 0;

    if (Math.abs(n) === Infinity) {
      n = 0;
    }

    // 6. If n >= len, return -1.
    if (n >= len) {
      return -1;
    }

    // 7. If n >= 0, then Let k be n.
    // 8. Else, n<0, Let k be len - abs(n).
    //    If k is less than 0, then let k be 0.
    k = Math.max(n >= 0 ? n : len - Math.abs(n), 0);

    // 9. Repeat, while k < len
    while (k < len) {
      // a. Let Pk be ToString(k).
      //   This is implicit for LHS operands of the in operator
      // b. Let kPresent be the result of calling the
      //    HasProperty internal method of O with argument Pk.
      //   This step can be combined with c
      // c. If kPresent is true, then
      //    i.  Let elementK be the result of calling the Get
      //        internal method of O with the argument ToString(k).
      //   ii.  Let same be the result of applying the
      //        Strict Equality Comparison Algorithm to
      //        searchElement and elementK.
      //  iii.  If same is true, return k.
      if (k in O && O[k] === searchElement) {
        return k;
      }
      k++;
    }
    return -1;
  };
}


if (!window.getComputedStyle) {
    window.getComputedStyle = function(el, pseudo) {
        this.el = el;
        this.getPropertyValue = function(prop) {
            var re = /(\-([a-z]){1})/g;
            if (prop == 'float') prop = 'styleFloat';
            if (re.test(prop)) {
                prop = prop.replace(re, function () {
                    return arguments[2].toUpperCase();
                });
            }
            return el.currentStyle[prop] ? el.currentStyle[prop] : null;
        }
        return this;
    }
}